<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <script src="jquery-3.3.1.min.js"></script>

    <title>Title</title>
</head>
<body>
<!--ul>li{php$$}*5-->
<ul>
    <li>php01</li>
    <li>php02</li>
    <li>php03</li>
    <li>php04</li>
    <li>php05</li>
</ul>
<!--<button type="button" name="button">click</button>-->
<input type="button" value="click">
</body>
<script>
    $(function () {
        $('input').click(function () {
            $("li").css('color','red')
            $('li').get(0).style.color='green' //转为了dom对象
            $('li')[1].style.color='gray'

        })
    })
</script>
</html>